Age at delivery, years | | | | |
≤20, n (%) | 1532 (1) | 526 (1) | 1006 (1) | 0.57 (0.51 to 0.64) |
21–30, n (%) | 59 350 (42) | 28 343 (42) | 31 007 (42) | 1 (reference) |
31–40, n (%) | 76 629 (54) | 37 043 (55) | 39 586 (54) | 1.02 (1.00 to 1.05) |
≥41, n (%) | 3465 (2) | 1584 (2) | 1881 (3) | 0.92 (0.86 to 0.99) |
Mean (SD) | 31 (5) | 31 (4) | 31 (5) | 1.03 (1.02 to 1.04) |
|
Socioeconomic status, n (%) | | | | |
Low | 38 618 (27) | 17 183 (25) | 21 435 (29) | 0.78 (0.76 to 0.80) |
Normal | 52 758 (37) | 26 734 (40) | 26 024 (35) | 1 (reference) |
High | 49 210 (35) | 23 449 (35) | 25 761 (35) | 0.89 (0.86 to 0.91) |
Unknown | 390 (0.3) | 130 (0.2) | 260 (0.4) | — |
|
Year of delivery, n (%) | | | | |
2004–2009 | 19 005 (13) | 6606 (10) | 12 399 (17) | 1 (reference) |
2010–2015 | 63 351 (45) | 27 558 (41) | 35 793 (49) | 1.45 (1.40 to 1.49) |
2016–2020 | 58 620 (42) | 33 332 (49) | 25 288 (34) | 2.47 (2.39 to 2.56) |
|
Ethnicity,a n (%) | | | | |
Caucasian | 122 630 (87) | 59 233 (88) | 63 397 (86) | 1 (reference) |
Non-Caucasian | 16 733 (12) | 7534 (11) | 9199 (13) | 0.88 (0.85 to 0.91) |
Unknown | 1613 (1) | 729 (1) | 884 (1) | – |
|
Preconceptional use of medication for chronic conditions,b n (%) | 46 825 (33) | 23 816 (35) | 23 009 (31) | 1.20 (1.17 to 1.22) |
|
Parity, n (%) | | | | |
0 | 58 771 (42) | 28 333 (42) | 30 438 (41) | 1 (reference) |
1 | 54 431 (39) | 25 850 (38) | 28 581 (39) | 0.97 (0.95 to 0.99) |
2 | 19 543 (14) | 9368 (14) | 10 175 (14) | 0.99 (0.96 to 1.02) |
≥3 | 7731 (5) | 3736 (6) | 3995 (5) | 1.00 (0.96 to 1.05) |
Unknown | 500 (0.4) | 209 (0.3) | 291 (0.4) | – |
|
Gestational age, weeks | | | | |
≤24, n (%) | 10 064 (7) | 2854 (4) | 7210 (10) | 0.40 (0.39 to 0.42) |
25–<28, n (%) | 352 (0.2) | 172 (0.3) | 180 (0.2) | 0.97 (0.79 to 1.20) |
28–<33, n (%) | 1480 (1) | 693 (1) | 787 (1) | 0.90 (0.81 to 0.99) |
33–<37, n (%) | 7765 (6) | 3689 (5) | 4076 (6) | 0.92 (0.88 to 0.97) |
≥37, n (%) | 121 315 (86) | 60 088 (89) | 61 227 (83) | 1 (reference) |
Mean (SD) | 38.0 (5.3) | 38.5 (4.3) | 37.5 (6.0) | 1.22 (1.21 to 1.23)c |
|
Care setting at start of pregnancy, n (%) | | | | |
Primary care | 120 592 (86) | 57 685 (85) | 62 907 (86) | 1 (reference) |
Secondary care | 20 109 (14) | 9694 (14) | 10 415 (14) | 1.02 (0.99 to 1.05) |
Unknown | 275 (0.2) | 117 (0.2) | 158 (0.2) | – |
|
Birth weight, g, mean (SD) | 3384 (653) | 3392 (641) | 3377 (665) | 1.02 (1.01 to 1.03)d |
|
Healthcare use in primary care | | | | |
Year before conception, mean (SD) | | | | |
Number of GP visits | 1.2 (2.4) | 1.4 (2.5) | 1.0 (2.2) | 1.09 (1.08 to 1.09) |
Number of GP prescriptions | 3.9 (4.7) | 4.2 (4.8) | 3.7 (4.7) | 1.02 (1.02 to 1.02) |
Number of incoming specialist letters | 1.7 (2.2) | 1.8 (2.3) | 1.5 (2.1) | 1.07 (1.07 to 1.08) |
During pregnancy, mean (SD) | | | | |
Number of GP visits | 1.0 (1.9) | 1.3 (2.1) | 0.8 (1.7) | 1.17 (1.16 to 1.18) |
Number of GP prescriptions | 2.8 (3.7) | 3.1 (3.7) | 2.5 (3.6) | 1.05 (1.04 to 1.05) |
Number of incoming specialist letters | 1.8 (2.1) | 2.3 (2.2) | 1.4 (1.9) | 1.23 (1.23 to 1.24) |